One method of fishing is known as the planer board system. In this method, a planer board is sent out from the side of the boat on the surface of the water. A positioning line secures the planer board to the boat. The positioning line angles out from the boat approximately 80 degrees from the direction of forward travel of the boat. The fishing lines are then attached with a release mechanism to the positioning line, and slid out that line to the desired distance away from the boat.
Another method of fishing is known as downrigger fishing. In this method, a downrigger cable serves as the positioning line, and it extends straight downward in the water from a boat on the surface. The cable includes a heavy (typically but not necessarily lead) weight at the end of the cable to keep the line vertical in the water while the boat moves forward for trolling. A fishing line from a fishing rod on the boat extends downward along the downrigger cable. The fishing line is attached in a releasable way to the cable at a desired depth below the surface of the water by some sort of conventional release mechanism.
In either case, when a fish strikes the hook on the fishing line, it pulls the fishing line free of the release mechanism. Suddenly, many feet of slack are in the line. For example, a typical total fishing line length may be approximately sixty feet, thirty feet from the end of the fishing rod to the release mechanism along the positioning line, and another thirty feet from the mechanism to the hook. This makes the shortest distance to the hook (i.e., the hypotenuse of the triangle) approximately forty-two feet. When the fish strikes and pulls the line away from the release mechanism, suddenly approximately eighteen feet of slack line is created. The slack line can provide the fish with enough play in the line to escape the hook. At a minimum, it takes the fisherman several (typically frantic) seconds to reel in the slack line, all the while attempting to keep the line taught so the fish will not escape.
While various devices to reduce the amount of slack line are in the prior art, there is a need for an improved downrigger and board line release apparatus that prevents the slack line, and thus results in more consistent retention of fish on the hook, and thus improved ability to play with the retained fish.